H2 the Electronic Potential Energy

The potential energy of an electron in a molecular orbital involves interactions of the electron with the two nuclei for the bonding orbital this is 

The negative signs in these expressions arise from the opposite charges on the electron and nuclei. 

The molecular potential energy must also take into account the nuclear-nuclear interaction, which is simply the Coulomb energy of the two protons  

Since these are to be treated as fixed point particles, this gives the potential energy of the nuclear-nuclear term directly. 

The symmetry of the molecule means that any integral involving Vi will have an equivalent from the V2 potential for example, = (5 2 V2 S 2)- This allows the set of 

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